1. Department of Informatics, University of Sussex, Brighton, BN1 9RH, UK
2. Wellcome Trust Centre for Neuroimaging, University College London, London, WC1N 3AR, UK
3. Department of Philosophy, and Dept of Informatics, University of Sussex, Brighton, BN1 9RH, UK
4. Department of Philosophy, Macquarie University, Sydney, NSW 2109, Australia